16556665205 has 8 divisors (see below), whose sum is σ = 19898059704. Its totient is φ = 13225291200.

The previous prime is 16556665127. The next prime is 16556665219. The reversal of 16556665205 is 50256665561.

It can be written as a sum of positive squares in 4 ways, for example, as 4750104241 + 11806560964 = 68921^2 + 108658^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-16556665205 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16556665205.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2501486 + ... + 2508095.

It is an arithmetic number, because the mean of its divisors is an integer number (2487257463).

Almost surely, 2^16556665205 is an apocalyptic number.

It is an amenable number.

16556665205 is a deficient number, since it is larger than the sum of its proper divisors (3341394499).

16556665205 is an equidigital number, since it uses as much as digits as its factorization.

16556665205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5010247.

The product of its (nonzero) digits is 1620000, while the sum is 47.

The spelling of 16556665205 in words is "sixteen billion, five hundred fifty-six million, six hundred sixty-five thousand, two hundred five".